Rotor shaft having damper member mounted thereon

Abstract

The drive shaft assembly for a centrifuge includes a resilient damper member mounted between a flexible shaft element and a bearing shaft element for rotation therewith. Vibrations imposed on the flexible shaft element by a centrifuge rotor are damped by the resilient damper member.

What is claimed is: 
     
       1. A centrifuge comprising: a rotor rotatable within a chamber about an axis of rotation;   a drive cartridge connected beneath the chamber;   a source of motive energy disposed within the cartridge;   a drive shaft assembly comprising a flexible shaft element connected to an axially contiguous hollow bearing shaft element, the flexible shaft element having one end thereof projecting into the chamber to receive the rotor thereon and a second end thereof projecting a predetermined distance into one end of the hollow bearing shaft element, the other end of the bearing shaft element being connected in a driven relationship with a source of motive energy; and   a damper arrangement mounted between the flexible shaft element and the bearing shaft element at a point along the flexible shaft element received within the bearing shaft element, the damper arrangement including a resilient member disposed between the exterior surface of the flexible shaft element and the interior surface of the bearing shaft element, the damper arrangement rotating with the drive shaft assembly and being operative to damp vibration imposed on the flexible shaft element by the rotor.   
     
     
       2. The centrifuge of claim 1 wherein the resilient member is mounted to the flexible shaft element at a point therealong adjacent the open end of the hollow bearing shaft element. 
     
     
       3. The rotor of claim 2 wherein the damper arrangement comprises substantially inverted cup shaped member having a central opening in the base portion thereof, the resilient member being mounted to the flexible shaft element at a point therealong substantially adjacent one end of the bearing shaft element such that the side wall of the cup shaped member overlies a portion of the exterior of the bearing shaft element, the resilient member being disposed intermediate the exterior surface of the flexible shaft element and the interior surface of that portion of the bearing shaft element overlaid by the sidewall of the cup shaped member. 
     
     
       4. The rotor of claim 2 wherein the damper arrangement comprises a substantially cylindrical sleeve having a central bore therethrough, the sleeve being mounted on the flexible shaft element at a point thereon substantially adjacent to one end of the bearing shaft element, the sleeve having a circumferential groove disposed on the exterior surface thereof, the resilient member being confined within the groove and disposed between the cylindrical sleeve and the interior surface of the bearing shaft element. 
     
     
       5. The rotor of claim 1 wherein the damper arrangement comprises substantially inverted cup shaped member having a central opening in the base portion thereof, the resilient member being mounted to the flexible shaft element at a point therealong substantially adjacent one end of the bearing shaft element such that the side wall of the cup shaped member overlies a portion of the exterior of the bearing shaft element, the resilient member being disposed intermediate the exterior surface of the flexible shaft element and the interior surface of that portion of the bearing shaft element overlaid by the sidewall of the cup shaped member. 
     
     
       6. The rotor of claim 1 wherein the damper arrangement comprises a substantially cylindrical sleeve having a central bore therethrough, the sleeve being mounted to the flexible shaft element at a point thereon substantially adjacent to one end of the bearing shaft element, the sleeve having a circumferential groove disposed on the exterior surface thereof, the resilient member being confined within the groove and disposed between the cylindrical sleeve and the interior surface of the bearing shaft element.